Piezoelectric transducers may be used to transmit electrical energy through various acoustic mediums, such as for example a metal wall. Electrical energy is converted into acoustic energy which propagates through the medium, which is then converted back into electrical energy at the receiving side of the system. Applications may include charging batteries and devices that operate in sealed or closed containers, for example. It is desirable for electrical energy to be provided from source to destination in an efficient manner utilizing piezoelectric transducers, and to provide transducers which may easily couple to an acoustic medium.